More stable princess cut diamond

ABSTRACT

A princess cut diamond having no points, but instead having rounded corners, so that the diamond is more stable, and has a less propensity to have any breakage.

RELATED APPLICATIONS

This application is a continuation-in-part of copending U.S. designpatent application Ser. No. 29/463,746 filed Feb. 21, 2014.

FIELD OF INVENTION

The present invention relates to a princess cut diamond not having anypointed corners so that the stone is more stable, and does not have apropensity to break or fracture.

BACKGROUND OF THE INVENTION

The princess cut is the second most popular cut shape for diamonds, nextto a round brilliant. The face-up shape of the princess cut is square orrectangular and the profile and side-on shape is similar to that of aninverted pyramid with four beveled sides. The standard princess cut hasthe same width as diameter of a round brilliant but will weigh more asit has four corners which would have otherwise been cut off and roundedto form a round brilliant. The princess cut while displaying the samehigh degree of brilliance, its faceting style is unique and completelydifferent than that of a round brilliant. The princess cut combines thehigh degree of light return of a round brilliant cut with a distinctivesquare or rectangular shape.

With regards to diamonds, when it comes to damage from chipping, roundis the safest shape. That's because it's basically a circle withoutlarge points protruding. The princess cut diamond, on the other hand issquare when viewed from the top. Four corners are exposed for damage.This shape is so vulnerable that some jewelry experts characterize it isan accident waiting to happen.

When setting the princess cut diamond in a setting, they are usually setin v prongs which cover the four corners of the princess cut diamond.

US D489,283 relates to a princess cut diamond.

U.S. Pat. No. 8,966,938 relates to a ring with a composite diamond headsetting that includes a head portion and a base portion. Inner and outerrim members of the ring have an off-centered orientation to facilitatethe head portion to have a larger thickness than the base portionwherein the inner rim defines a circular boundary of hollow space withinthe ring adapted to define a finger size of the ring. The head portionincludes a first channel structure that includes an indentation that ispositioned with a plurality of multiple shaped diamonds through aninvisible setting means in a juxtaposition arrangement to form aclustered diamond head that creates an illusion of a big diamond

U.S. Pat. No. 8,813,519 relates to a modified princess cut diamond andmethod of forming a modified princess cut diamond into a symmetricalshape possessing hearts and arrow pattern in a round cut diamond.

US D605,973 relates to a princess cut diamond design.

U.S. Pat. No. 7,140,199 relates to a mounting system for cut stones inthe form of a setting that encloses, supports and visually enhances acut stone such as a princess cut diamond.

U.S. Pat. No. 6,745,596 relates to a princess cut gemstone having apavilion, a girdle, and a crown. In a preferred embodiment, the princesscut gemstone is a diamond with 101 facets, a pavilion of 64 facets, agirdle of 4 facets and a crown with 33 facets.

US Patent Publication No. 2011/0203317 relates to a jewelry articleswith a gem invertedly set therein. A cut gem having a top and bottom isset into the jewelry article in an inverted position such that thebottom of the cut gem faces out to be viewed. The jewelry article maycomprise a plurality of cut gems and a center gem. The jewelry articlehas a substantially star shape when the article is viewed.

US Patent Publication No. 2005/0005639 relates to a jewelry piece havinga precious stone having a visible upper surface and a body extendingbelow the upper surface, the body having facets that meet to fromcorners, each facet having a groove at each corner that extends from thecorner along only a portion of the facet so that the grooves of thefacets that form each corner meet at the corner.

US Patent Publication No. 2003/0010058 relates to a princess cutgemstone having a pavilion, a girdle, and a crown. It is preferred thatthe princess cut gemstone is a diamond with 101 facets, a pavilion of 64facets, a girdle of 4 facets and a crown with 33 facets.

US Patent Publication No. 2009/0183525 relates to a gemstone including asubstantially rectangular girdle, a crown extending in a first directionfrom the girdle and a pavilion extending in a second direction from thegirdle opposite the first direction. The gemstone has 65 uniquelyarranged and angled facets, 25 of which are in the crown, and 40 ofwhich are in the pavilion. The crown has four sides, a table, and fourbezel facets, each positioned at a respective corner of the crown. Eachof the four sides of the crown have a first break extending from thegirdle toward the table, a second break extending from the first breaktoward the table, a third break extending from the second peak to thetable, and a pair of star facets provided between the third break andbezzle facets on each respective corner of the crown.

US Patent Publication No. 2005/0081563 relates to a method of cutting agemstone known as a riemer cut. The gemstone has a crown portion, apavilion portion characterized by having four main pavilion facets and aculet base and girdle portion provided between the crown portion andpavilion portion. The main pavilion facets are integrally formed withthe culet base created a pavilion facet base. The riemer cut isapplicable to all shapes of stones including round, square, oval,marquee, pair shaped and rectangular diamonds.

SUMMARY OF THE INVENTION

The present invention relates to a princess cut diamond wherein saiddiamond has no points. It is an object of the present invention for thecorners on the princess cut diamond to be rounded corners. When aprincess cut diamond having points is set, such that the prongs are ontop of or covering the pointed corners, a large amount of pressure isput on the pointed corners causing a high risk of breakage on thepointed corner as well as on the whole stone.

Pointed corners at the manufacturing level are harder to set since thereis only one point. There is more surface area available for setting whenthere is a rounded corner.

It is an object of the present invention for the rounded corners to besmall enough so that once a prong is set upon each corner, visuallythere is no difference when looking straight up on whether the corner isrounded or pointed. Indeed, when a user looks at the top of the diamondwithin the setting, the user cannot tell if the corners are rounded orpointed.

Diamond cutters slice corners on a straight line. In the presentinvention, the pointed edges disappear.

It is an object of the present invention to provide a princess cutdiamond that has less breakage. Insurance writers will not insureprincess cut diamonds because of the risk of breakage due to the pointedcorners. Princess cut diamonds made by the present invention would morelikely be insured.

It is an object of the present invention to maximize the square shape ofthe stone.

It is an object of the present invention to maximize dimensions of thetop surface of the stone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a top view of the princess cut diamond of the presentinvention.

FIG. 2 shows a side view of the princess cut diamond of the presentinvention.

FIG. 3 shows a side view of the princess cut diamond of the presentinvention.

FIG. 4 shows a bottom view of the princess cut diamond of the presentinvention.

FIG. 5 shows a top view of the princess cut diamond of the presentinvention.

FIG. 6 shows a top view of a prior art design.

FIG. 7A is a top view of a prior art design of a princess cut diamondhaving pointed corners, without the setting and in the setting.

FIG. 7B is a top view of the princess cut diamond of the presentinvention with the rounded corners without the setting and in thesetting.

FIG. 7C is a top view of a prior art design of a square-shaped cushioncut diamond without a setting and in a setting, with part of the largerounded corners visible under the prongs of the setting.

DETAILED DESCRIPTION

FIG. 1 shows a princess cut diamond 10 having rounded corners 12, 14,16, and 18. These rounded corners 12, 14, 16, and 18 may be for exampleslightly rounded corners. The princess cut diamond 10 does not have anypointed corners so that the stone is more stable, and does not have apropensity to break or fracture. Pointed corners at the manufacturinglevel are harder to set since there is only one point. There is moresurface area when there is a rounded corner. As a consequence, it evenbecomes possible for a jewelry manufacturer to use delicate or thinprongs to securely set the princess cut diamond of the present inventionto a setting/mounting. Prongs used for the setting of princess cutdiamonds do not have to be thick, large or V-shape anymore for theprincess cut diamonds to be securely set. The rounded corners of theprincess cut of the present invention may thus be easily and fullycovered and securely set by fine and high-end thin prongs which have theadvantage to show more of the diamond material and less of the gold usedto set it. The rounded corners of the princess cut of the presentinvention may be small enough so that even if a thin and/or delicateprong is set upon each corner, visually there may be no difference whenlooking straight up on whether the corner is rounded or pointed.

FIG. 2 shows a side view of the princess cut diamond 10.

FIG. 3 shows a side view of the princess cut diamond 10.

FIG. 4 shows a bottom view of the princess cut diamond 10 having roundedcorners 12, 14, 16 and 18.

FIG. 5 shows a further princess cut diamond 20 having rounded corners22, 24, 26, and 28. The rounded corners have a smaller surface area thanthe rounded corners of princess cut diamond 10 of FIG. 1. For example,rounded corners 22, 24, 26 and 28 may be rounded to a minimum sufficientso that the princess cut 20 may be securely set to a high end jewelrysetting/mounting comprising very thin or delicate prongs.

FIG. 6 shows a prior art princess cut diamond 30 having pointed corners32, 34, 36 and 38. When the princess cut diamond having points is set,such that the prongs are on top of or covering the pointed corners, alarge amount of pressure is put on the pointed corners causing a highrisk of breakage on the pointed corner as well as on the whole stone.Many insurance writers may not insure the type of princess cut diamondsbecause of the risk of breakage due to the pointed corners. Moreover,the pointed corners at the manufacturing level are harder to set sincethere is only one point.

FIG. 7A is a top view of a prior art design of a conventional princesscut diamond 60, and a top view of the prior art design with the pointedcorners 64, 66, 68 and 70 covered by prongs 72, 74, 76 and 78 of asetting 62. The four pointed corners are exposed for damage during orafter setting.

FIG. 7B is a top view of the princess cut diamond 40 of the presentinvention, and a top view of the princess cut diamond with the roundedcorners 44, 46, 48 and 50 covered by prongs 52, 54, 56 and 58 of asetting 42. In a preferred embodiment, the rounded corners (e.g. roundedcorners 44, 46, 48 and 50 of FIG. 7B) are small enough, and/or roundedapproximately to a minimum, so that once a prong is set upon each corner(e.g. prongs 52, 54, 56 and 58 of FIG. 7B):

-   -   1) Visually there is no difference when looking straight up on        whether the corner is rounded or pointed. For example, the        princess cut diamond 40 of the present invention may look        identical to the prior art design of princess cut diamond 60 of        FIG. 7A with pointed corners once it is mounted in the setting        42, and even if the prongs used to set the princess cut of the        present invention are delicate/thin prongs; and    -   2) The stone is more stable, and does not have a propensity to        break or fracture (e.g. princess cut diamond 40 of FIG. 7B), and    -   3) The dimensions of the face-up surface of the princess cut of        the present invention (e.g. princess cut diamond 40 of FIG. 7B)        are equal, and/or substantially equal, to the dimensions of the        face-up surface of a prior art design of a princess cut diamond        with pointed corners (e.g. princess cut diamond 60 of FIG. 7A)        once both of the diamonds are mounted in a similar setting (e.g.        similar settings 62 of FIG. 7A and 42 of FIG. 7B).

FIG. 7C is a top view of a prior art design of a square-shaped cushioncut diamond 80, and a top view of the prior art design with part of thelarge rounded corners 84, 86, 88 and 90 being visible under the prongs92, 84, 96 and 98 of a setting 82. A square-shaped cushion cut diamond(e.g. square-shaped cushion cut diamond 80) may have at least thefollowing different characteristics from the princess cut of the presentinvention (e.g. princess cut diamond 40 of FIG. 7B):

-   -   1) It comprises larger rounded corners which are still in part        visible under the prongs of a setting (e.g. large rounded        corners 84, 86, 88 and 90 being visible under the prongs 92, 84,        96 and 98 of a setting 82). Indeed, unlike the princess cut        diamond of the present invention (e.g. princess cut diamond 40        of FIG. 7B), the square-shaped cushion cut does not look        identical to the prior art design of a princess cut diamond with        pointed corners (e.g. prior art design of princess cut 60 of        FIG. 7A) once it is mounted in a setting (e.g. setting 42).        Moreover, it may look even less similar to the prior art design        of a princess cut diamond with pointed corners if the prongs        used to set said square-shaped cushion cut diamond are        delicate/thin prongs; and    -   2) The dimensions of the face-up surface of the square-shaped        cushion cut diamond, in the instance it is set or not set, are        substantially smaller to the dimensions of the face-up surface        of the princess cut diamond of the present invention since its        rounded corners are at least substantially larger than the        rounded corners of the princess cut diamond of the present        invention. For example, the square-shaped diamond 80 and the        princess cut diamond 40 of the present invention have the same        width and length dimensions at their center, but the diametrical        distance between the prongs of said square-shaped diamond 80        (e.g. diametrical distance between prongs 98 and 94) is smaller        to the diametrical distance between the prongs of said princess        cut diamond 40 of the present invention (e.g. diametrical        distance between prongs 58 and 54).

1. A princess cut diamond comprising: a diamond in the shape of a squareor a rectangle having four sides and four corners; each of said fourcorners being rounded corners wherein said corners do not have anypoints; said rounded corners being of a size that when placed in asetting said corners are covered by said setting; said diamond having acrown and a pavilion with four beveled sides.
 2. The diamond of claim 1,wherein said princess cut diamond is within said setting, said a usercannot tell if said corners are rounded or pointed because settingcovers said corners.
 3. The diamond of claim 1, wherein said roundedcorners of said princess cut diamond do not have a propensity to breakor fracture during or after setting.
 4. The diamond of claim 1, whereinthere is more surface area available for setting at said rounded cornersof said princess cut diamond than at pointed corners of a conventionalprincess cut diamond.
 5. The diamond of claim 1, wherein said roundedcorners of said princess cut diamond are fully covered and securely setusing prongs.
 6. The diamond of claim 1, wherein dimensions of face-upsurface of said princess cut diamond are equal to dimensions of face-upsurface of a princess cut diamond with pointed corners once saidprincess cut diamond and said princess cut diamond having pointedcorners are mounted in a similar setting.
 7. The diamond of claim 1wherein said four corners of said princess cut diamond are rounded andsymmetrical, creating a homogeneous and uniform shape.